/XRL/4

JMPP

2043CH32

 

 

 

 

 

493

58

 

 

 

 

 

493

 

 

 

 

 

 

 

Headings

 

 

 

 

id

File

Page

References

REDBCOM

REDB$COM

 

 

 

 

 

xxii

Comments Welcome

PLNG

2043IMBD

 

 

 

 

 

1

Part

1, Planning the Migration - An Introduction

 

 

 

 

3, 3, 3

TREAS

2043CH01

 

 

 

 

 

4

1.2, Traditional Reasons for Migrating

 

 

 

 

3

FREAS

2043CH01

 

 

 

 

 

10

1.3, Functional Reasons for Migrating to OS/390

 

 

 

 

3

INTSIZ

2043CH02

 

 

 

 

 

13

2.1, Introduction to Sizing

 

 

 

 

13

CPS

2043CH02

 

 

 

 

 

18

2.2, OS/390 Components/Products/Subsystems

 

 

 

 

13, 416, 539

SIZCHGS

2043CH02

 

 

 

 

 

24

2.3, What Changes Between VSE and OS/390?

 

 

 

 

13

SIZWHO

2043CH02

 

 

 

 

 

26

2.4, Who is Affected by This Migration?

 

 

 

 

13

APMIG

2043CH02

 

 

 

 

 

27

2.5, Approaches to Migration

 

 

 

 

13

MIGSTR

2043CH02

 

 

 

 

 

27

2.5.2, OS/390 Conversion and Production Implementation

 

 

 

Strategies

OVERV

2043CH02

 

 

 

 

 

29

2.5.3, VM/ESA Guest Support in Your VSE to OS/390

 

 

 

Migration

SIZEDU

2043CH02

 

 

 

 

 

31

2.6, Educational Requirements

 

 

 

 

13, 481

WKSCOPE

2043CH02

 

 

 

 

 

32

2.7, Scope of Work and Challenges

 

 

 

 

13, 481, 481, 482

OCT02

2043CH02

 

 

 

 

 

33

2.7.3,

JCL Conversion

 

 

 

 

482

FILEMIG

2043CH02

 

 

 

 

 

35

2.7.4,

File Migration

 

 

 

 

482

SIZCOST

2043CH02

 

 

 

 

 

38

2.8, Cost Considerations

 

 

 

 

13

DEVPLAN

2043CH03

 

 

 

 

 

41

Chapter 3, Developing the Plan

 

 

 

 

481, 481, 494, 494

HMC3OV

2043CH03

 

 

 

 

 

41

3.1, Overview

 

 

 

 

41

HMPROST

2043CH03

 

 

 

 

 

43

3.1.2.6, Project Staffing

MIGPLG

2043CH03

 

 

 

 

 

45

3.2, Plan Components

 

 

 

 

41

HMC3PMC

2043CH03

 

 

 

 

 

49

3.3, Progressive versus Mass Conversion

 

 

 

 

41

OCT01

2043CH03

 

 

 

 

 

51

3.3.7, Standardized Conversion Deliverables and Automation

 

 

 

 

481

MIGSAMP

2043CH03

 

 

 

 

 

53

3.4, Plan Examples

 

 

 

 

41, 42

MIGXMP

2043CH03

 

 

 

 

 

56

3.4.2,

Project Plan Example

 

 

 

 

47, 482

CVSE390

2043IMBD

 

 

 

 

 

67

Part

2, Converting the VSE Operating System to the OS/390

 

 

 

Operating System

 

 

 

 

3, 3

JCL

2043CH04

 

 

 

Page 650
Image 650
IBM OS/390 manual XRL/4

OS/390 specifications

IBM OS/390, a versatile operating system, was a cornerstone in enterprise environments and played a pivotal role in mainframe computing. Released in the mid-1990s, OS/390 combined the strengths of IBM's MVS (Multiple Virtual Storage) with new features and enhancements, targeting scalability, reliability, and performance in demanding business applications.

One of the key features of OS/390 was its robust support for multiple users and processes. The system allowed thousands of concurrent users to access applications and data, ensuring high availability and minimizing downtime—a critical requirement for many large organizations. This scalability was supported through various enhancements in memory management and processor scheduling, enabling optimal resource allocation across diverse workloads.

OS/390 was known for its superior workload management capabilities. The Workload Manager (WLM) component allowed administrators to define service policies, specifying how system resources would be allocated according to the priority of tasks. This ensured that critical business processes received the necessary resources while less critical tasks were managed more flexibly.

Another significant characteristic of OS/390 was its commitment to security. The operating system provided comprehensive security features, including user authentication, data encryption, and auditing capabilities. This focus on security was vital for organizations handling sensitive data, ensuring compliance with regulations and safeguarding against unauthorized access.

OS/390 also supported advanced technologies that facilitated integration and development. The system included features like the IBM CICS (Customer Information Control System) for transaction processing and IMS (Information Management System) for database management. These technologies allowed organizations to build robust, high-performance applications tailored to specific business needs.

The ease of network integration was another strength of OS/390. With the advent of the Internet and global connectivity, OS/390 systems could easily interface with various network protocols, enabling businesses to operate in a connected world. This inclusion paved the way for many organizations to expand their capabilities and offer new services, driving digital transformation.

In conclusion, IBM OS/390 represented a significant advancement in mainframe technology, combining scalability, security, and robust workload management. Its rich feature set and support for critical enterprise applications solidified its role as a vital component of many organizations' IT infrastructures, ensuring they could meet their operational challenges head-on while supporting future growth. As technology continues to evolve, the legacy of OS/390 remains influential in the realm of computing.